Two effects relevant for the study of astrophysical reaction rates: gamma transitions in capture reactions and Coulomb suppression of the stellar enhancement

TL;DR

This paper discusses two key effects—gamma transition energies and Coulomb suppression—that influence the calculation and measurement of astrophysical reaction rates, impacting nucleosynthesis modeling.

Contribution

It introduces the concept of Coulomb suppression of the stellar enhancement factor, revealing that certain reactions are more experimentally accessible than previously thought.

Findings

Coulomb suppression reduces stellar enhancement for some reactions.

Gamma transition energies are crucial for reaction rate calculations.

Reactions with negative Q value can be more favorable for experiments.

Abstract

Nucleosynthesis processes involve reactions on several thousand nuclei, both close to and far off stability. The preparation of reaction rates to be used in astrophysical investigations requires experimental and theoretical input. In this context, two interesting aspects are discussed: (i) the relevant gamma transition energies in astrophysical capture reactions, and (ii) the newly discovered Coulomb suppression of the stellar enhancement factor. The latter makes a number of reactions with negative Q value more favorable for experimental investigation than their inverse reactions, contrary to common belief.